Members of Congress are calling on Nvidia Chief Executive Jensen Huang to resign, and committee chairs say they may subpoena him if he does not agree to testify, CNBC reported Wednesday.

Sen. Kevin Cramer, a Republican from North Dakota and a member of the Senate Banking Committee, told CNBC, “As a matter of his own conscience, he should resign,” citing Huang’s admission of an affair with a woman whom news outlets have reported U.S. intelligence believes is a Chinese spy. “This is a guy that’s right now so vulnerable to extortion, blackmail. I just don’t think, as a national security matter, we can run the risk,” Cramer said. Rep. Suhas Subramanyam, a Virginia Democrat on the House Oversight Committee, told the network, “Jensen Huang should resign from Nvidia.” Rep. Don Bacon, a retiring Nebraska Republican, said, “From the little I know, yes,” when asked whether Huang should step down: “He allowed himself to get compromised by the Chinese government. Not good.”

The comments came on the deadline set by three House committee chairs — GOP Reps. Brian Mast, John Moolenaar and Rick Crawford — who asked Huang in a Nov. 4 letter to appear on Nov. 18. Mast and Moolenaar told reporters Wednesday afternoon that they had not yet heard from Huang and were giving him until the end of the day to respond. Asked whether they would consider a subpoena, Mast said “yes,” and Moolenaar said “all three committees have subpoena power.” Subramanyam told CNBC that investigations should examine “what was going on with Nvidia and China” and “why the administration did nothing about it even though they appeared to have known,” including “what influence the money from Nvidia and Jensen Huang had.” Sens. Elizabeth Warren and Jim Banks, in a statement quoted by CNBC, urged colleagues to attach the AI Overwatch Act to this year’s defense bill, saying Huang’s confirmation of the relationship “makes these national security concerns even more urgent.”

This account is based on CNBC’s reporting and on-camera comments. It is separate from Wednesday’s Wall Street Journal report that Nvidia’s board is preparing to consider removing Huang, which the company has not confirmed. No resignation or subpoena had been announced in CNBC’s story.